Nie F.,Dalian University of Technology | He D.,Dalian University of Technology | Guan J.,Dalian University of Technology | Bao H.,Dalian University of Technology | And 4 more authors.Energy and Fuels | Year: 2017

Urea hydrolyser is an important device for power plants choosing urea as a primary reactant in flue gas denitration. According to literature surveys and theory analyses on the chemical reaction, this study analyzed the influence of feed concentration and operation conditions on the hydrolytic production. Meanwhile, the kinetic empirical formula of the reaction was obtained (frequency factor A 8.23×1011, while activated energy equals to 98.09 kJ/mol). Kinetic characteristics together with phase-equilibrium model were utilized to simulate the behavior of an imported hydrolyser. The calculation result was well accorded with the operation history, verifying the reliability of the analysis. The conclusion can be used as the guideline to the research and design of domestic hydrolyser for DeNOx projects in China.

Four different sizes of pre-bend designs were performed for a 1.2 MW wind turbo-generator blade. While numerical simulation was made for its flow field using SST κ-ω turbulence models, during which the influence of pre-bending size on wind turbo-generator power output was obtained, and thus an appropriate pre-bending size was determined. Results show that the wind turbo-generator power output reduces nonlinearly with growing pre-bending size, and the pre-bending profile can effectively regulate the wind turbo-generator power output when wind speed changes. For a pre-bending size of 0.6 m, the design power of 1.2 MW can be reached with only a relative error of 0.0006%. However, the interaction induced by blade rotation is inevitable.

The simulated earthquake experimental study on a large desulfurization tower was carried out using shaking table test. A 1:15 reduced-scale thin-walled steel structure model of the desulfurization tower was designed for testing and the dynamic responses of the model were discussed. The responses of peak acceleration were studied under a sine wave, Tianjin wave and Hyuga seismic wave in various angles and the most unfavorable input angle was analyzed. The results show that the influence of the input angle of an excitation wave can not be ignored, the maximum influence is in the direction of 30° and the minimum is in the direction of 60°. The complexity of the thin-wall desulfurization tower can affect the dynamic characteristics of the structure to a great extent. The weight of the tower top is one of the main factors causing the distribution of peak acceleration uneven in tower height.

In this paper, blades of a 1.2MW wind turbine were designed based on MATLAB programming by using the preflex method. Four blades were respectively designed by un-bended, and with the preflex sizes being 0.3, 0.6 and 0.9 meters, and the SST k-ω turbulence model was adopted to simulate them. The optimum preflex size of the blade was selected after comparing the effects of the preflex sizes on the output power. The results shown that: the output power of un-bended turbine is larger than design power and the relative error is 2.48%, the 0.9 meter's output is less than design power with the relative error of 3.9%, and the 0.6 meter's output approaches the design power with the relative error of 0.0006%. The output power of the wind turbine decreases following with the increase of the preflex sizes, and the characteristics is not linear.